National Laboratory Pathfinder - Vaccine - Survey (NLP-Vaccine-Survey) - 07.28.16

Overview | Description | Applications | Operations | Results | Publications | Imagery

ISS Science for Everyone

Science Objectives for Everyone
National Laboratory Pathfinder - Vaccine - Survey (NLP-Vaccine-Survey) investigation uses microgravity to examine several pathogenic (disease causing) microorganisms to assist in the development of potential vaccines for the prevention of infections on Earth and in microgravity.
Science Results for Everyone
Four pathogens walk into a bar –er, space – and come out weaker. Researchers evaluated whether microgravity affects the ability of four common harmful bacteria – Listeria, MRSA, Enterococcus, and Candida – to kill nematodes, microscopic roundworms common in soil. Results indicate that spaceflight reduces the virulence or strength of these microorganisms. Previous studies have associated microgravity with increased virulence of some microbes; this is the first investigation performed in space to indicate reduced virulence. The data will help evaluate the risks that pathogens pose to astronauts in space and could help fight the diseases such organisms cause on Earth.

The following content was provided by Timothy G. Hammond, M.B.B.S., and is maintained in a database by the ISS Program Science Office.
Experiment Details


Principal Investigator(s)
Timothy G. Hammond, M.B.B.S., Durham Veterans' Affairs Medical Center, Durham, NC, United States

Information Pending

BioServe Space Technologies, University of Colorado, Boulder, CO, United States

Sponsoring Space Agency
National Aeronautics and Space Administration (NASA)

Sponsoring Organization
National Laboratory (NL)

Research Benefits
Information Pending

ISS Expedition Duration
April 2009 - October 2009

Expeditions Assigned

Previous Missions
The NLP-Vaccine series of investigations began on STS-123/1JA during ISS Expedition 16.

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Experiment Description

Research Overview

  • Pathogenic (disease causing) microorganisms cause numerous illnesses worldwide, many times resulting in death. In the United States (U.S.), adverse effects caused by these pathogenic organisms cost billions of dollars annually to treat. There is currently no vaccine available for many common forms of pathogenic organisms.

  • The National Laboratory Pathfinder - Vaccine - Survey (NLP-Vaccine-Survey) sends several species of microorganisms to space to determine the next step to take to create a vaccine for these life-threatening microbes.

  • The pathogenic organisms and Caenorhabditis elegans worms are launched separated, then serially mixed, grown and fixed in flight. Once the experiment is completed on orbit and returned to Earth, analysis of virulence is completed by the investigator.

The 2005 NASA Authorization Act designated a portion of the International Space Station (ISS) as a National Laboratory. To fulfill that mandate, NASA is providing an opportunity for non-governmental entities to conduct research and development and potentially industrial processing on board the ISS. These opportunities aboard the ISS are considered National Lab Pathfinder (NLP) missions. These NLP missions launch to the ISS on each available shuttle mission, until the shuttle is retired.

The National Laboratory Pathfinder - Vaccine - Survey (NLP-Vaccine-Survey) investigation grows several microorganisms, including Pseudomonas aeruginosa, Klebsiella pneumonia, Proteus mirabilis, Streptococcus pneumoniae, Listeria monocytogenes, Entrococcus faecalis and Candida albicans in microgravity to affect the virulence (infection potential) and assist in the development of a vaccine to treat the illnesses caused by the microbes. Details about each microorganism in NLP-Vaccine-Survey are as follows:

  • Pseudomonas aeruginosa is a common bacterium which causes disease in humans. It is ubiquitous and thrives not only in normal atmospheres, but also with little oxygen, and has thus colonized many natural and artificial environments. The symptoms of the infections are generalized inflammation. If infection occurs in critical body organs such as the lungs, the urinary tract, and kidneys, the results can be fatal.

  • Klebsiella is a gram-negative bacteria that can cause infections in healthcare settings, including pneumoniae, bloodstream infections, wound or surgical site infections, and meningitis.

  • Proteus mirabilis is a gram-negative bacterium commonly found in the human intestinal tract as part of normal human intestinal flora. In hospital settings, it is not unusual for gram-negative bacilli to colonize both the skin and oral mucosa of both patients and hospital personnel.

  • Streptococcus pneumoniae causes many clinical syndromes, depending on the site of infection, e.g., acute otitis media, pneumonia, bacteremia, or meningitis.

  • Listeriosis, a serious infection caused by eating food contaminated with the bacteria Listeria monocytogenes is an important public health problem. The disease affects the elderly population, pregnant women, newborns, and adults with weakened immune systems. There is currently no vaccine available for Listeriosis infections.

  • Enterococcus species are hardy organisms that can survive and grow in many environments. With increasing antibiotic resistance, Enterococci are feared pathogens that can be challenging to treat.

  • Candida albicans lives in numerous parts of the body as normal flora. However, when an imbalance occurs, such as hormone changes, C. albicans can multiply, resulting in a mucosal or skin infection called Candidiasis.

Each flight opportunity of this investigation provides additional insight about the bacteria and the changes that are occurring as they grow in space. The knowledge is applied to streamline and accelerate the development of vaccines and therapeutics on Earth.

The microbes and the Caenorhabditis elegans worms are launched separated and serially mixed, grown and fixed in flight. Once the experiment is completed on orbit and returned to Earth, analysis of virulence is completed by the investigator. NLP-Vaccine-Survey was flown on the Space Shuttle during the last servicing mission for Hubble on STS-125 in May 2009. NLP-Vaccine-Survey was flown on the Space Shuttle to the ISS as NLP-Vaccine-3.

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Space Applications
Results from this experiment may help scientists more clearly understand measures that should be taken to reduce the risk of infection and contraction of disease while in space.

Earth Applications
There is currently no vaccine available for the strains of organisms being examined; this research may help develop vaccines against these life threatening organisms.

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Operational Requirements and Protocols
This payload is conducted under ambient temperature conditions and does not require image or data download.
The research is contained in the Fluid Processing Apparatus (FPA). In order to activate the samples, the crew turns a hand crank that has been inserted onto the top of the GAP which contains the FPAs. Once the samples are activated for a predetermined length of time, the crew again turns the hand crank on top of the GAPs to terminate the experiment. The terminated samples are returned to Earth via the shuttle.

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Decadal Survey Recommendations

Information Pending

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Results/More Information

Microgravity affects the human body, but it also changes the physical characteristics of germs. For examples, fungus grown in simulated microgravity turn more rapidly from single cells to a filamentous type, form biofilm communities and become more resistant to antifungal agent which suggest increased virulence. Salmonella bacteria grown in space and returned as live cultures also appear to be more virulent when injected into mice. Studying microbes’ reaction to space living helps to evaluate risks to astronauts from possible changes in bacterial virulence, and in addition, the knowledge obtained is relevant to infections on Earth. Simultaneous studies were performed with spaceflight, clinorotation device (simulated microgravity culture chamber), and static ground controls. Four common harmful bacteria - Listeria monocytogenes, methicillin-resistant Staphylococcus aureus (MRSA), Enterococcus faecalis, and Candida albicans - were evaluated to see if microgravity affects their ability to kill Caenorhabditis elegans (C. elegans) nematodes (microscopic roundworms commonly found in soil). Listeria is typically a food-borne pathogen responsible for gastroenteritis, meningoencephalitis, and spontaneous abortions. Enterococcus causes urinary tract infections, endocarditis, and meningitis. Candida infections range in severity from vaginitis to septic shock. MRSA infections are one of the most prevalent and costly infectious conditions within the health care system. Since natural diet of C. elegans is bacteria and fungi in the soil, the worms are killed after eating harmful bacteria in their presence; thus the quantity of surviving microorganisms becomes an indicator of worm mortality and hence virulence. Analytical results of the population density of worms and bacteria grown under the three different conditions indicate that spaceflight appears to reduce virulence of diverse microorganisms, including Listeria, Enterococcus, Candida, and MRSA for both larvae and adult roundworms. These are the first data, acquired with a direct in vivo assay system in space to demonstrate virulence, showing that spaceflight is associated with reduced virulence.

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Results Publications

    Hammond TG, Stodieck LS, Birdsall HH, Becker JL, Koenig PM, Hammond JS, Gunter MA, Allen PL.  Effects of Microgravity on the Virulence of Listeria monocytogenes, Enterococcus faecalis, Candida albicans, and Methicillin-Resistant Staphylococcus aureus. Astrobiology. 2013 November; 13(11): 1081-1090. DOI: 10.1089/ast.2013.0986.

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Ground Based Results Publications

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ISS Patents

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Related Publications

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Related Websites
BioServe Space Technologies
Media Advisory - NASA Studies Microbes on Space Shuttle Flight
Payoffs from ISS Research
VA Research Project on NASA Space Shuttle

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image NASA Image: S119E006157 - Astronaut John Phillips, STS-119 mission specialist, works with Group Activation Packs (GAP) on the middeck of Space Shuttle Discovery during flight day two activities.
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image This is a photomicrograph of the fungus Candida albicans. Image courtesy of the Centers for Disease Control and Prevention, Image ID - 2918.
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image This scanning electron micrograph depicts numbers of bacteria, which are identified as being Gram-positive Enterococcus sp. bacteria. Image courtesy of the Centers for Disease Control and Prevention, Image ID - 209.
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image Electron micrograph of a Listeria bacterium in tissue. Listeria monocytogenes is the infectious agent responsible for the food borne illness Listeriosis. Image courtesy of the Centers for Disease Control and Prevention, Image ID - 10828.
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image This is a colorized scanning electron micrograph of Pseudomonas aeruginosa bacteria. Image courtesy of the Centers for Disease Control and Prevention, Image ID - 10043.
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image This is a colorized scanning electron micrograph of Streptococcus pneumonia. Image courtesy of the Centers for Disease Control and Prevention, Image ID - 9996.
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